Some strands of composite fiber-optic ground wire (OPGW) are sometimes melted and broken by high-energy lightning strikes. DC arc tests simulating lightning strikes have been performed to obtain the ...melting and breaking characteristics of OPGW strands. The tests have to be performed under many conditions concerning the arc (e.g., current, duration, polarity, gap length) and the OPGW (e.g., size, type, and number of strands) to clarify the melting and breaking characteristics of the strands. In this paper, the calculations regarding the melting characteristics of strands are performed considering the transferred heat and its area from the arc to the strands under the aforementioned conditions. The melting characteristics of strands are calculated with an arc current of 1-100 kA considering the measured current of actual lightning. The calculation results of the strand melting duration depending on arc current show good agreement with the experimental values obtained in dc arc tests.
Bioassays of six racemic synthesized candidate sex pheromone compounds against male New World screwworm Cochliomyia hominivorax (Coquerel) flies showed that the most potent bioactivity was found with ...6-acetoxy-19-methylnonacosane and 7-acetoxy-15-methylnonacosane compared with four other isomeric acetoxy nonacosanes and a larger aliphatic ketone. As all these methyl-branched compounds have two asymmetric carbons and four possible enantiomers, characterization of the natural enantiomers was essential. All four enantiomers for the two most bioactive isomers of the natural sex pheromone were synthesized for bioassay. Hydrolysis and derivatization of these enantiomers with different fluorescent reagents was followed by column-switched high-performance liquid chromatography. The use of two linked, reversed-phase columns of different polarity held at sub-ambient temperatures allowed good separation of each enantiomer. This analysis applied to natural material was successful, as (6R,19R)-6-acetoxy-19-methylnonanocosane, and (7R,15R)- and (7R,15S)-7-acetoxy-15-methylnonanocosane were detected in extracts of recently colonized female flies.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
Metal ignition wires are widely used in power arc tests on insulator sets and similar. Finer metal ignition wire is preferred from the point of view of influence on the apparatus tested. However, if ...the metal ignition wire is too fine, the arc cannot be sustained. To perform a power arc test successfully, therefore, the metal ignition wire needs to have some degree of thickness. With these requirements in mind, we proposed a novel arc ignition method that allows the use of an extra fine wire by leading to the pre-arc in a current of several dozen amperes. In this paper, the sustainment characteristics of arc ignited from an extra fine copper wire using this novel method were investigated with a gap between the rod electrodes. The results showed that the kiloampere-class arc with a gap length of meter class could be ignited through pre-arc from the copper wire that is 0.03 mm in diameter with a voltage of 12 or 24 kV. The influence of the copper wire thickness on arc characteristics was also studied by comparing the arcs ignited by this novel method with those ignited by the general method where copper wires exceeding 0.3 mm in diameter were used.
In vitro and oral administration challenge trials were performed to search for effective agents derived from natural sources (natural agents) against infections by the monogenean
Heterobothrium ...okamotoi in the tiger puffer
Takifugu rubripes. First, four drugs (praziquantel, levamisole, pyrantel pamoate and antimony sodium tartarate) were screened for their anthelmintic efficacy against
H. okamotoi to select the drug most suitable as an effective positive control for a challenge trial of natural agents. Of these, praziquantel showed anthelmintic efficacy against
H. okamotoi in both in vitro and challenge trials and the in-feed praziquantel (4 g/kg basal diet) was chosen as the positive control. Next, four natural agents (caprylic acid, orange oil, peppermint oil and cinnamon oil) were screened. Of these, caprylic acid, peppermint oil and cinnamon oil had an efficacy against larvae of the
H. okamotoi in in vitro trials. In the challenge trials, when each natural agent (2.5 g/kg basal diet) that was effective in vitro trials were also given to the fish in feed, caprylic acid and praziquantel prevented horizontal infection. Furthermore, the survival of groups treated with caprylic acid and praziquantel were significantly higher than the negative control (basal diet) and the other groups. Additionally, the number of matured parasites on the branchial cavity wall of fish, which was assumed to exist from the beginning of the challenge trials, decreased in the groups treated with caprylic acid and praziquantel. Our results show that caprylic acid has an anthelmintic efficacy against
H. okamotoi.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The duration of the majority of Alcohol Rehabilitation Programs (ARP) at major hospitals specializing in this treatment is three months. Recently, however, because of diverse backgrounds and patients ...needs, long periods of hospitalization have become difficult. In response to this, Okamotodai Hospital initiated a one-month ARP program three years ago. One feature of this program is that it can be freely structured to meet the requirements of individual patients. This study compares the prognosis of patients treated under this one-month program with that of those who have undergone the three-month program. A group of 56 patients who had completed a one-month ARP program during a period of two to three years was compared with a group of 46 patients who had completed a three-month program over a similar period. The backgrounds of the subjects were researched by questionnaire. A comparison of the prognosis of patients in the respective programs showed there was no statistical difference, with a recovery rate of 45% for both programs. Results of this study statistical difference, with a recovery rate of 45% for both programs. Results of this study cannot be generalized, due to the lack of subjects and recovery of questionnaires. Since enforcement of the one-month ARP, increasing number of patients have been using the program. This fact doesn't necessarily show that the use of ARP improve, although the possibility remains that utilization of the one-month ARP is promoted. In recent years, utilization of brief intervention has been demonstrated and recovery from alcoholism in the outpatient clinics reported. Considering such things, results of the study show that the one-month ARP is a valid and effective program.
Induction of hematopoiesis in an embryonic germ (EG) cell line derived from mouse primordial germ cells (PGCs) was examined. When single undifferentiated EG-1 cells were inoculated directly into the ...methylcellulose medium, both primitive and definitive erythropoiesis were seen in embryoid bodies derived from the EG cells as observed in ES cells, and production of myeloid cell lineages was stimulated by IL-3. These results indicate that EG cells acquired in vitro potency to differentiate toward hematopoietic cells, although they were derived from PGC and are distinct from inner cell mass-derived ES cells with regard to gene expression and patterns of DNA methylation corresponding to genomic imprinting. It turns out that they are useful for study of cell differentiation in the animals whose ES cells are not available.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Recent years, some distributed generations such as energy storage systems or renewable energy sources have been introduced in distribution systems, and the voltage violation problem has been at stake ...by the reverse power flows from the load to the generator. In this paper, we consider NAS (natrium sulfur = sodium sulfur) battery systems to be utilized for not only energy storage but also power system control, and propose a new voltage control strategy in order to provide the proper sending voltage at distribution substations. First, the current flows at each distribution feeder are individually measured, and the sending voltage is calculated by using V-I characteristics, which indicate the relationship between the sending voltage and the current flows at each distribution feeder. Next, active and reactive power outputs of the NAS battery system are determined by solving an optimal power flow calculation in order to realize the predetermined sending voltage. Numerical examinations have been carried out using a 52-bus example system model to verify the validity of the proposed method, and successful results have been obtained.
Metal strands of OPGWs (composite fiber-optic ground wires) installed in overhead power transmission lines are sometimes melted and broken when struck by high-energy lightning. This paper presents ...the calculation results regarding OPGW strands melting behavior when struck by DC arcs simulating high-energy lightning. The calculations revealed that the melted volume of the strand was 26% of the strand volume before the arc test, i.e. the rate of the non-melted volume of the strand was 74%. On the other hand, the residual tensile strength of the melted strand was 69% of the other non-melted strands after DC arc test. These results suggest there is a strong correlation between the calculated non-melted volume of the strand and the measured residual tensile strength of the melted strand.
Recently, as power system loads are located farther away from power plants and are more unevenly distributed, reactive power losses have tended to increase due to the heavier power flow with high ...load growth and long distance transmission. Therefore, an effective voltage control scheme has been brought to attention in a considerable number of studies. Hence, We propose on-line voltage stability control schemes, i.e. a preventive control and an emergency preventive control, in addition to conventional local controls. In order to assess the effect on voltage stability in different generators, we propose the voltage instability proximity index including three power flow equations in a specified value space (VIPIt) based on the conventional index VIPI.
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